[IMPALA-5839] nullifzero and zeroifnull documentation about return type doesn't match implementation

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Impala 3.1.0
• Component/s: Docs
• Epic Color: ghx-label-3
• Assignee: Alexandra Rodoni
• Reporter: Philip Martin
• Created: 24/Aug/17 20:05
• Updated: 07/Aug/18 21:32
• Resolved: 07/Aug/18 19:19

Description

https://impala.incubator.apache.org/docs/build/html/topics/impala_conditional_functions.html mentions return types of nullifzero and zeroifnull:

nullifzero(numeric_expr)
Return type: same as the initial argument value, except that integer values are promoted to BIGINT and floating-point values are promoted to DOUBLE; use CAST() when inserting into a smaller numeric column

zeroifnull(numeric_expr)
Return type: same as the initial argument value, except that integer values are promoted to BIGINT and floating-point values are promoted to DOUBLE; use CAST() when inserting into a smaller numeric column

However, I see it returning the underlying type without promotion.

[...:21000] > select typeof(nullifzero(1)), typeof(zeroifnull(cast(1 as integer)));
...
+-----------------------+------------------------------------+
| typeof(nullifzero(1)) | typeof(zeroifnull(cast(1 as int))) |
+-----------------------+------------------------------------+
| TINYINT               | INT                                |
+-----------------------+------------------------------------+
Fetched 1 row(s) in 0.02s

I suspect the docs are wrong here.